Composites Formed by Recycled Polypropylene and Wet-Blue Leather Waste: A Sustainable Practice

Much research has been carried out around the development of alternative materials with the most varied purposes aiming at a positive contribution to the environment through the use of solid waste. Among these solid contaminants, the one produced in industrial effluent treatment stations, such as tanneries, stands out, where leather processing has a negative environmental impact, since the chemicals used in the treatment of raw materials, including chromium salts, have a high degree of toxicity. These residues can be used in the manufacture of alternative materials to promote the reduction of the environmental impact generated by them. Therefore, this study aimed to verify the feasibility of incorporating waste produced in a tannery effluent treatment station, known as “leather powder”, in a polymeric matrix of recycled polypropylene in the proportions of 10 and 20%, by means of making specimens by extrusion and injection processes. The specimens were analyzed in relation to the mechanical tests of tensile strength and Izod impact. The specimens containing 10 and 20% of leather powder had their resistance increased by 2.10 and 7.65% with respect to traction, 9.7 and 24.59% with respect to impact, respectively. The homogeneous distribution of leather powder particles in the polymeric matrix may have contributed to the increase in mechanical strength. This homogeneity was verified by the morphological analyzes. Thus, it is feasible to insert leather powder in recycled polypropylene in the proportions of 10 and 20%, presenting itself as a solution for the proper disposal of these residues, thus having a favorable contribution to the environment.